Why The Biggest "Myths" About Audi G28 Could Actually Be True
How to Replace an Audi G28 Engine Speed Sensor
Charles the Humble Technician teaches how to replace the G28 Engine Speed Sensor. This sensor is situated on the outside of the transmission just above the flywheel gear. It transmits a signal to the ECU via the grey wire (T55/49) which is then sent to the tachometer in the instrument cluster.
1. Engine Speed Sensor
The sensor is located at the edge of the transmission, above the flywheel ring gear, the G28 Engine Speed Sensor sends a signal to ECU pin T55/49 via a grey wire. The ECU utilizes this information to control the amount of fuel and boost. It also sends an indication to the G5 Tachometer located in the instrument cluster.
The sensor is used to connect with the G40 Camshaft position Sensor. The ecu must be aware when the crankshaft is TDC and where the camshaft is so it can trigger spark and injectors in the right way.
If this sensor fails, the ECU will throw the P00160 error, which means the Crank Shaft and Intake Camshaft aren't in sync, possibly indicating the chain is stretched or a jump link on the upper timing chain. The code won't appear without the additional information supplied by other sensors (G4 or G40).
Testing is a bit tricky since there are two connector pins and they perform different functions but the best method of testing it is by measuring resistance between the sensor and the ECU. It should read approximately 1000 ohms if the sensor is in full operation. Look for signs of coolant, or oil in the connector bay if there are problems with this part.
2. Injectors
Yesterday accelerating full speed from highway paytoll, I experienced a big cut in power as if the engine was running out of gas or injectors aren't firing at all. This morning i pull out the spark plugs, three were drenched in gazoline, the fourth was dry. I put a piece of tissue over each hole in the injector and when I start the engine without sparks, the three that have gazoline pop right out. The 4th one stays closed. I tested the ground connection on ECU pins 14/55, 30/55 and 48/55. I get zero ohm. I'm assuming the issue is somewhere else.
I also tried to reset the PID without success. The car will start when the G28 is unplugged, and it works fine when the G28 connected. However the intermittent misfire issue continues to occur at higher RPM. The coolant sensor (G62), even if it is not plugged in, shows temperatures of -49c. Also i noticed that the oil pressure gauge in the cockpit shows 2 bar while the actual pressure is 0.0 if i crank up the engine.
I'm not sure what to do. I believe that I've ruled everything else out. But i am afraid I might have missed something. Please let me know should you have any suggestions! TIA!
3. Fuel Pump
The fuel pump of the g28 receives a signal from the RPM sensor. The GM-style transmitter is the same as the G4 and both function in the 80 100 200, UrS and RS2 cars which is why you can easily locate one at a junkyard or in a local parts store. Testing them is easy - put your DMM in resistance mode and measure the resistance between pins 1 (with the bump on the connector's end up) and 2 (2nd from the left on the black end of the connector). They should be infinite Ohms.
4. ECU
Our 20vt turbo (3B AAN, ABY, and ADU) engines have an ECU that has to know the position and speed of the crankshaft to make decisions regarding timing of the fuel injectors, etc. In order to do this it makes use of a Crank Position Sensor (G4) and an Engine Speed Sensor (G28). If you encounter a problem with either of these sensors, the diagnostic scanner will display codes that could cause an engine shut down.
Some of the symptoms of a malfunctioning G28 sensor include an inaccurate rev counter for the gearbox and gears that shift faster than normal, and/or a misfire when in gear. If you experience any of these issues, it is likely your sensor is deteriorating and requires replacement car key audi. The good news is that they are very cheap and readily available particularly in the case of an Bosch model, like ours. Alternatively, GM's version of this component is an excellent choice.
5. Tachometer
A failing engine speed sensor could be the cause of a slew of issues with your car. It's a crucial component of the transmission in your audi replacement car keys because it relays information to the ECU on how fast or slowly the car's engine is spinning. When this sensor fails, it can cause problems for the transmission as well as the rest of the car's components.
The G5 engine sensor is located near the edge of the transmission, over the flywheel ring. It transmits a signal via an uncolored wire to the ECU pin T55/49. The ECU utilizes this signal to regulate the amount of fuel and boost, and also to timigrate. It also transmits it to the G5 Tachometer inside the instrument cluster. You can check the sensor for any failure by checking the continuity between it and the tachometer, between the ECU pin T55/49 and the instrument cluster connection to pin T6a/1 (trace [79trace [79]) and between T6a/1 and the instrument cluster pin T26a/12. You should observe approximately 1000 ohms resistance between those two pins. This is a common part across the audi spare key cost 80 100, 200, UrS and RS2 range from 1985 MC through the 1997 UrS AAN and 1995 RS2 ADU, so the best parts could be found in wrecking yards.